Patch "irqchip/gic-v4: Make sure a VPE is locked when VMAPP is issued" has been added to the 6.6-stable tree

DISCUSSION Marc Zyngier 2 participants 2 messages Sep 8, 2024 1 message not in the archive Stable branch

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Marc Zyngier

author

2024-09-08 15:27 UTC #1 lore raw

Quoted 54 lines · Sasha Levin

This is a note to let you know that I've just added the patch titled
irqchip/gic-v4: Make sure a VPE is locked when VMAPP is issued
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
irqchip-gic-v4-make-sure-a-vpe-is-locked-when-vmapp-.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.
commit 1a232324773145ff7ce59b6a1b52b3247223f9d4
Author: Marc Zyngier <[email protected]>
Date:   Fri Jul 5 10:31:55 2024 +0100
irqchip/gic-v4: Make sure a VPE is locked when VMAPP is issued
[ Upstream commit a84a07fa3100d7ad46a3d6882af25a3df9c9e7e3 ]
In order to make sure that vpe->col_idx is correctly sampled when a VMAPP command is issued, the vpe_lock must be held for the VPE. This is now possible since the introduction of the per-VM vmapp_lock, which can be taken before vpe_lock in the correct locking order.
Signed-off-by Marc Zyngier <[email protected]>
Signed-off-by Thomas Gleixner <[email protected]>
Tested-by Nianyao Tang <[email protected]>
Link https://lore.kernel.org/r/[email protected] open here
Signed-off-by Sasha Levin <[email protected]>
drivers/irqchip/irq-gic-v3-its.c +3 -1
index e25dea0e50c7..1e0f0e1bf481 100644
@@ -1804,7 +1804,9 @@ static void its_map_vm(struct its_node *its, struct its_vm *vm)
 		for (i = 0; i < vm->nr_vpes; i++) {
 			struct its_vpe *vpe = vm->vpes[i];
 
-			its_send_vmapp(its, vpe, true);
+			scoped_guard(raw_spinlock, &vpe->vpe_lock)
+				its_send_vmapp(its, vpe, true);
+
 			its_send_vinvall(its, vpe);
 		}
 	}
@@ -1825,8 +1827,10 @@ static void its_unmap_vm(struct its_node *its, struct its_vm *vm)
 	if (!--vm->vlpi_count[its->list_nr]) {

drivers/irqchip/irq-gic-v3-its.c static void its_unmap_vm(struct its_node *its, struct its_vm *vm) · line 1836

Quoted 10 lines

drivers/irqchip/irq-gic-v3-its.c +3 -1

 		int i;
 
-		for (i = 0; i < vm->nr_vpes; i++)
+		for (i = 0; i < vm->nr_vpes; i++) {
+			guard(raw_spinlock)(&vm->vpes[i]->vpe_lock);
 			its_send_vmapp(its, vm->vpes[i], false);
+		}
 	}
 
 	raw_spin_unlock_irqrestore(&vmovp_lock, flags);

No please.

Not only you are missing the essential part of the series (the patch introducing the per-VM lock that this change relies on), you are also missing the fixes that followed.

So please drop this patch from the 6.6 and 6.1 queues.

M.

Signature · 1 line

Without deviation from the norm, progress is not possible.

Sasha Levin

maintainer

2024-09-08 22:21 UTC #2 lore raw

Quoted 69 lines · Marc Zyngier

Quoted 54 lines · Sasha Levin
This is a note to let you know that I've just added the patch titled
irqchip/gic-v4: Make sure a VPE is locked when VMAPP is issued
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
irqchip-gic-v4-make-sure-a-vpe-is-locked-when-vmapp-.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.
commit 1a232324773145ff7ce59b6a1b52b3247223f9d4
Author: Marc Zyngier <[email protected]>
Date:   Fri Jul 5 10:31:55 2024 +0100
irqchip/gic-v4: Make sure a VPE is locked when VMAPP is issued
[ Upstream commit a84a07fa3100d7ad46a3d6882af25a3df9c9e7e3 ]
In order to make sure that vpe->col_idx is correctly sampled when a VMAPP command is issued, the vpe_lock must be held for the VPE. This is now possible since the introduction of the per-VM vmapp_lock, which can be taken before vpe_lock in the correct locking order.
Signed-off-by Marc Zyngier <[email protected]>
Signed-off-by Thomas Gleixner <[email protected]>
Tested-by Nianyao Tang <[email protected]>
Link https://lore.kernel.org/r/[email protected] open here
Signed-off-by Sasha Levin <[email protected]>
drivers/irqchip/irq-gic-v3-its.c +3 -1
index e25dea0e50c7..1e0f0e1bf481 100644
@@ -1804,7 +1804,9 @@ static void its_map_vm(struct its_node *its, struct its_vm *vm)
 		for (i = 0; i < vm->nr_vpes; i++) {
 			struct its_vpe *vpe = vm->vpes[i];
 
-			its_send_vmapp(its, vpe, true);
+			scoped_guard(raw_spinlock, &vpe->vpe_lock)
+				its_send_vmapp(its, vpe, true);
+
 			its_send_vinvall(its, vpe);
 		}
 	}
@@ -1825,8 +1827,10 @@ static void its_unmap_vm(struct its_node *its, struct its_vm *vm)
 	if (!--vm->vlpi_count[its->list_nr]) {
drivers/irqchip/irq-gic-v3-its.c static void its_unmap_vm(struct its_node *its, struct its_vm *vm) · line 1836
Quoted 10 lines
drivers/irqchip/irq-gic-v3-its.c +3 -1
 		int i;
 
-		for (i = 0; i < vm->nr_vpes; i++)
+		for (i = 0; i < vm->nr_vpes; i++) {
+			guard(raw_spinlock)(&vm->vpes[i]->vpe_lock);
 			its_send_vmapp(its, vm->vpes[i], false);
+		}
 	}
 
 	raw_spin_unlock_irqrestore(&vmovp_lock, flags);
No please.

Quoted 5 lines

Not only you are missing the essential part of the series (the patch introducing the per-VM lock that this change relies on), you are also missing the fixes that followed.
So please drop this patch from the 6.6 and 6.1 queues.

Will do, thanks!

Signature · 2 lines

Thanks,
Sasha